This is a new submission for a broad based predoctoral training program in developmental biology. The program takes advantage of the programmatic infrastructure established through a highly successful 15 year long training grant in developmental biology that expired in 2014. The proposed training program requests 12 trainee slots per year. Each year 6 trainees will be appointed for a duration of 2 years so that at any given time the training program will include 6 trainees in their first and 6 trainees in their second year of support (12 trainee slots/year). The proposed training program includes faculty from multiple schools and departments within the University and reflects a major and continuing expansion of developmental biology research and training. The new plan emphasizes laboratory research directed towards basic mechanisms of embryonic development using a diversity of vertebrate, invertebrate, and plant organisms. It fosters the application of modern genetic, genomic, cellular, molecular and high resolution imaging approaches to developmental studies. Research training areas include transcription and cell signaling mechanisms that control cell lineage determination, differentiation, migration, organogenesis, cellular senescence, morphogenesis, pattern formation, epigenetic regulation of developmental processes, and stem cell biology. Trainees are encouraged to explore clinical research areas including cancer and genetic diseases of development. In preparation for their research training, predoctoral students receive formal instruction in an established curriculum of study, including lecture courses in developmental biology and advanced seminars on genetic, cellular, and molecular approaches to developmental mechanisms and disease. Students will also participate in developmental biology journal clubs, a developmental biology seminar series that includes student invited speakers, research discussion groups on selected topics, and in annual scientific symposia. Trainees present their research findings at departmental seminars, local symposia and national conferences. Finally, the training program will provide trainees with dedicated a) semiannual Show and Tell research days where trainees will lecture other trainees about their project followed by a hands-on demonstration of research techniques employed by the trainee presenter, e.g. live cell imaging, b) a yearly retreat to present their work in a more formal settig that includes an eminent external speaker who will help evaluate this training program, c) crafting of an Individual Development Plan and its yearly review by the Directors, d) Professional development seminars, such as mini-writing classes tailored to graduate students, e) quarterly lunchtime discussion with a Penn faculty of the trainee's choice to ask questions about the faculty's field of research and/or to discuss general issues such as lab management or career path decisions, f) brief `job shadowing' internships in pharmaceutical, translational, or other settings to explore different aspects of working in the pharmaceutical/biotech sector.